ACIS CTI Ground Correction
ACIS software to correct to CTI implemented and verified in pipeline. Disabled, awaiting RMF.
Response Matrix:
- A new FEF has been developed for S3 @ -120 C which incorporates the improved interpolation around the Si-K edge.
- Completed evaluation of new S3 -110 C matrix which demonstrates the new matrix is significantly better.
- Evaluation of new matrices is underway.
- Continue work on a new method of FEF and RMF generation which should reduce the amount of time and labor necessary to produce matrices for the CTI-corrected FI data.
- Evaluating results of MIT team which indicates that the gain of the BI CCDs is a sensitive function of incident flux at low energies. This raises a large issue of how one generates RMFs when the response depends on the incident flux in general.
- SOT/SDS/DS are discussing implementation & possible software development for use with factorizing the response of CTI-corrected frontside chips into a no-CTI ideal CCD response and a CTI effect. Two approaches were discussed:
- Fit the ideal CCD response as it is currently done, and involve with the CTI effect matrix; or
- Interpolate the ideal CCD response (and CTI matrix) from smoothed versions of the MIT instrument simulator pulse height spectra.
- Work is proceeding on approach 1.